Fuse indicator



Nov. 11, 24- 1,514,642

E. W. WERDEN FUSE INDICATOR Filed Nov. 18 1922 5 IN VENTOR dwa/zd wfifimdmv A TTORNE Y5 Patented Nov. 11, 1924.

UNITED STATES PATENT OFFICE.

EDWARD W. WERDEN, OF MOUNT VERNON, NEW YORK, ASSIGIIOR TO EDWARD TAYLOR WERDEN, OF MGUNT VERNON, NEW YORK.

FUSE INDICATOR.

Application filed November 18, 1822.

To 6415 whom it may concern:

Be it known that I, EDWARD lVHrrrLn lVnRDnN, a citizen of the United States of America, residing at Mount Vernon, New York, have invented a new and useful Fuse Indicator, of which the following is a specification.

My invention relates to a fuse indicator.

In the indicating fuses with which I am familiar, it very often happens that when the fuse blows, the intended indication does not become apparent, and the indicating purpose of the fuse is defeated.

It is the general object of my invention to overcome the objections heretofore noted and to provide an indicator fuse which will give a visible indication when the fuse blows and will therefore be reliable in operation.

Briefly stated, in the preferred form of my invention, ther is provided a fuse of any suitable, or preferred type. I supplement the main current carrying fusible element in the fuse, with a relatively small, high resistance element, connected in parallel with the main fusible element. After the main fuse element has been destroyed by an overload or short circuit, the current passes through the high resistance element and when the latter is fused, a visible indication is given.

In the drawings, which show for illustrative purposes only, preferred forms of my invention,

Fig. 1 is a longitudinal, sectional view of a fuse embodying features of my invention.

Fig. 2 is an enlarged, sectional view, taken substantially in the plane of the line 22 of Figure 1.

Fig. 3 is a relatively enlarged fragmentary View of a fuse, illustrating features of the invention.

Fig. 4 is a fragmentary sectional View, illustrating a modified form.

In said drawings, 5 indicates the usual, or any, cesired form, of fuse cartridge. Fuse contacts in the form of ferrules 6, 7 are provided on the fuse cartridge. The main fuse member 8 is held within the cartridge between the usual end pieces 9, 10, which are soldered or otherwise connected to the fuse contacts. A fuse, as thus de scribed, is a form well known in the art.

The cartridge 5 is preferably provided with a groove 11 therein, which in the form Serial No. 601,860.

shown, extends from end to end thereof. A relatively small, high resistance element 12 is positioned in the groove 11, and extends to and makes contact with both fuse contacts or ferrules. In order to provide a good contact, I prefer to deposit a drop of solder on the junction between the ferrules and the high resistance element as indicated at 13, 14; in Figures 1, 2 and 3. It will thus be seen that the high resistance element 12 is electrically connected to and in parallel with the main fuse member 8.

It is desirable to cover the high resistance element or shunt 12, with some material which will enhance or amplify the indication given when the high resistance element bur 'ns out. This covering may be of such material as translucent or transparent paper which will char upon the burning out of the element 12, but I have found that shellac, such as is indicated at 15, in Figure 3, makes a suitable covering for the high resistance element. and upon burning of the latter, the shellac will either materially change its color or bubbles will form there in, so that an indication that the fuse has blown, will be given.

In the form shown in Figure 4 the high resistance element 12, instead of being directly mechanically connected to the ferrules, passes under the latter, and the mechanical connection is made by means of solder 16, which connects the main fuse member 8 and the ferrules.

It will be seen that in both forms, herein described, the high resistance element lies substantially, wholly on the outside of the fuse cartridge and will therefore be visible.

In operation, when a sufficiently high overload or short circuit occurs, the main fuse member 8, will first fuse. During the normal operation of the fuse, the element 12, due to its high resistance. will carry very little current but upon the breaking of the current through the main fuse member, the current passing through the high resistance element 12, will immediately fuse the same, and since this element 12, preferably lies substantially, wholly on the outside of the fuse cartridge, a positive, visible indication will be given.

If the high resistance shunt element is not covered, the indication of blowing of the main fuse is indicated by the absence of, or a break in, the shunt 12. Since the element 12 is rather delicate, it is usually preferable to provide some sort of indicating covering, such as has been previously described.

From the above description it will be seen that since the high resistance shunt connection lies substantially, wholly on the outside of the fuse cartridge, a sure indication of the blowing of the fuse will be given.

While I have described preferred forms of my invention I'WlSll it understood that changes and modifications may be made within the scope of the appended claim.

I claim: In a fuse, a fuse cartridge, contacts on the ends'of said cartridge, a fuse member Withthe outside of said cartridge and connected to said contacts, said high resistance element being embedded in a substantially transparent substance lying within and substantially filling said groove, wherebysaid high resist ance element will be protected and will be visible for 'its' entire length between said contacts.

EDWARD -W. WERDEN, 

